The invention relates to a check valve, comprising a housing with an inlet opening and an outlet opening, with a cage-like insert disposed therein as a support for a spring element and for guiding a closing body, which can be moved against the spring element and can be moved between a first end position, in which it lies in contact with a seat, forming a seal, and a second end position, in which the valve is completely open.
Such a check valve is used wherever liquids must be prevented from flowing through in one direction. Such valves are used, for example, in engines, in which they are connected in the oil cycle.
A known check valve comprises a housing, into which the liquid may enter and from which it may emerge. In the interior of the housing, there is a cage-like insert, which is frequently constructed in the form of a trihedral, which has a support for a spring element, usually a spiral spring, which is disposed centrally and parallel to the axis in the valve housing and which forces the closing body in the form of a metal ball against the seat in the region of the inlet opening. When the pressure at the inlet opening is sufficiently high, the ball is moved against the restoring force of the spring, so that the valve opens up, the degree of opening depending on the hydraulic pressure or flow existing. As described, the ball is guided at the cage-like insert, which usually has three guiding surfaces parallel to the axis. Because of its shape, the ball lies in contact with the guiding surfaces of the insert with only a very small surface. To ensure a high flow cross-section, the guiding surfaces are dimensioned relatively narrow, so that a certain radial movement is possible.